CLASSIFICATION OF BACTERIA 27 



Genus 3. Sarcina. Cell-division in three planes ; 



cubical packets produced. (Fig. 9.) 

 4. Planococcus. Motile micrococci. 

 5. Planosarcina. Motile sarcinae. 



Family II. BACTERIACE^. Cells more or less 

 elongated, cylindrical, and straight, without an 

 enclosing sheath. Division at right angles to 

 long axis of cell. 



Genus I. Bacterium. Longer or shorter rods, non- 

 motile. Without endospores. 

 2. Bacillus. Longer or shorter rods, motile. 

 Flagella distributed all over the cell : 

 forms endospores. (Fig. 8.) 



3. Pseudomonas. Longer or shorter rods, 

 motile. Flagella polar, i.e. arranged 

 at ends of the cell. (Fig. 8.) 



Family III. SPIRILLACE^:. Cells elongated, curved, 

 or spiral, without enclosing sheath. Usually 

 motile. 

 Genus I. Spirosoma. Cells rigid, not motile. 



2. Microspira. Cells rigid, motile usually 



with one polar flagellum. 



3. Spirillum. Cells rigid, screw form (Fig. 

 5), motile with bunch of polar flagella. 

 (Fig. 8.) 



Family IV. CHLAMYDOBACTERIACE^:. Cells rod- 

 shaped, in chains, surrounded by a common 

 gelatinous sheath. (Fig. 28.) 



Several ill-defined genera distinguished, e.g. Creno- 

 thrix, Sphcerotilus (Cladothrix], and others. 



Order II. THIOBACTERIA. In this group the cells 



